Charger plug with improved package

ABSTRACT

A reduced plug-size charger plug for power conversion is disclosed utilizing a pair of blades that are slidably mounted into a charger housing, obviating the need for insertion molding. To promote and maintain electrical contact while minimizing package size and charger plug cost, a pair of spring contacts are provided for electrically connecting the blades with internal circuitry.

FIELD OF THE INVENTION

The invention relates to charger plugs and, in particular, to a plug forelectronic devices, and, more particularly, a power converting plug forportable electronic devices, the plug having an improved package bysimplifying the construction and reducing the size of the package.

BACKGROUND

Currently, portable electronics and other devices are provided electricenergy via a plug provided with prongs or blades that are inserted intoa power outlet. Often, the plug provides some type of power conversionor conditioning, etc., so that the power delivered to the electronicdevice is in a state that is usable by the electronic device. Mostparticularly, the plug acts as a converter so that power received fromthe plug of a certain voltage, as well as preferably a certain currenttype (i.e., alternating current or direct current) is transmitted to theelectronic device with a pre-determined voltage and current type.Towards this end, the plug may receive, e.g., 120 VAC and supply astepped-down voltage as a direct current, such as 5-20 VDC. The plug, asdescribed, is thus a converter plug and, for electronic devices that areportable and chargeable, the plug is commonly referred to as an acadapter or charger plug. In order to effect such power conversion, theplug includes internal circuit components, the components then beingelectrically connected to a power coupling such as a cord that extendsfrom the plug.

There are significant issues with such plugs, such as the size of theplug. Efforts to reduce the plug vertical and lateral dimensions arewell-known so that, when the plug prongs are inserted into a powerreceptacle or outlet or power strip (a power source), the plug itselfprovides little or no interference with use of an adjacent receptacle.Often times, however, plug designs having reduced vertical and lateraldimensions require an increased plug length (i.e., the dimension of theplug aligned with the direction of the plug prongs). This increasedlength may hinder the ability of a user to locate the plug in an outletthat is behind, for instance, a furniture item, and may require the plugto protrude in a manner that makes the plug susceptible to being struck,that makes the plug susceptible to backing out of the receptacle due tothe torque provided by its own weight, or that makes the plug simplyunsightly.

Another issue with such plugs is cost, which is typically a two-foldproblem. One aspect of the problem is that packaging material costs fora larger plug are simply greater than for a smaller plug.

The other aspect of the problem is the cost of manufacturing andassembling the plug. In many prior art plugs, the blades (including theprongs receivable in the outlet) are insert molded, which is arelatively expensive process and requires approximately 20 seconds ofmold time. To be more specific, the process requires the blades to bepositioned in proper registry within a mold cavity. The mold thenreceives the material for a plug housing in a flowable state (such as bytransfer or injection molding, as examples). The material then cools andhardens so that the blades and housing portions can be removed. Becausethe temperature of the metal blades is elevated, the molding must becooled sufficiently that the blades do not cause creep in thethermoplastic creep material, which requires time. Nonetheless, errorsdo result from improper positioning or inadvertent movement of theblades during the molding process, which results in production waste, atleast in terms of time and effort.

After the blades are insert molded, they must be joined with theinternal circuitry of the plug, that is, the circuitry that provides thepower conversion. In most prior art plugs, this requires hand solderingwithin the plug housing to join connections on the blades with eitherwires leading to the circuitry or with contacts directly located on thecircuitry, such as a printed circuit board (PCB). This process ismanually performed and requires patience and care, which translates tolabor and time. This process can also result in errors as it isdifficult to avoid contact of a solder iron or other implement fromcontacting the plastic housing (resulting in damage thereto), and as itis difficult to immediately recognize improper solder joints.Additionally, it is difficult to test the plug device for properoperation until after the blades are soldered/secured with thecircuitry, at which point removal of defective components is laborintensive.

It should also be noted that use of solder and hookup wire requirespackaging space. That is, utilizing solder and hookup wire forelectrically connecting the blades to the circuitry requires a minimumsolder joint, at least for reliability purposes as well as typically forpractical purposes as it is difficult to utilize a small amount ofsolder. The wire length needs to be long enough to allow soldering whilethe components are separated. This length of wire takes up space insidethe package and can get in the way when closing the package.Accordingly, the packaging and, more precisely, the housing or body ofthe plug must accommodate such solder joints and hookup wire, resultingin a larger plug package size or dimension directly attributable to thesolder joints and hookup wire.

One example of a plug having internal circuitry for AC conversion to DCis described in U.S. Pat. No. 6,644,984, to Vista, Jr., et al. Notably,the '984 patent is directed towards reducing the package size and theprofile of the plug, as well as eliminating the need for flexible wiresor direct soldering between the blades and the circuitry, whichpurported results in quicker assembly.

Nonetheless, the various forms of the '984 patent have an elongated pluglength due to the manner of connecting the blades with the circuitry.Each of the forms described has a forward body portion in which theblades are mounted, the blades having a rearward extension that isconnected, without solder, with contact terminals on a PCB. Each of thecontact terminals requires an fore-to-aft extended structure for eitherforming a leaf spring biased against the blade or supporting areceptacle for receiving a portion of the blade therethrough. In eachform, then, the configuration and construction of the blades and thecontact terminals require additional length for the plug size andpackage. Furthermore, the structures for the contact terminals require acertain amount of material and are stamped into form.

The '984 patent also requires additional components and manufacturingsteps. While the forms illustrate a manner of connecting the bladeswithout the use of solder, the designs still require blades that areinsert molded into the forward body portion. In the simplest form, themanufacturing steps include first securing the PCB in a rearhousing/body portion in proper alignment, then advancing the rear bodyportion and PCB toward and into engagement with the forward body portionand blades molded therein, whereupon the body portions are secured. Inmore complicated designs, the forward body portion first receives thePCB, and the sub-assembly is then mounted into a clamshell-type rearbody portion having top and bottom halves.

Accordingly, there has been a need for an improved plug package designwith a reduced size and improved manufacturability.

SUMMARY

In accordance with an aspect, a charger plug is disclosed includinginternal circuitry for converting input electrical power to outputelectrical power, a housing comprising upper and lower halves definingan interior space for the internal circuitry, an input assemblyincluding prong portions for connecting with a power outlet and at leastone leg portion, wherein at least one of the upper and lower halvesincludes an opening for slidably receiving each leg portion, and a pairof electrically conducting spring contacts in biased engagement withrespective portions of the input assembly for receiving input electricalpower therefrom, the spring contacts in electrical connection with theinternal circuitry.

In some forms, the input assembly includes a pair of electricallyconducting blade members including respective prong portions, a portionof each blade member being received in respective openings in the upperand lower halves. The upper and lower halves may each include a pair ofblind openings oriented generally vertically for receiving respectiveportions of the blade members therein for securing the blade members.The spring contacts may be mounted on the internal circuitry and bebiased against a portion of the blade members.

In some forms, the input assembly includes first and second blademembers including respective prong portions, each of the blade membershaving a portion rearwardly located from the prong portions and slidablyreceived in openings in each of the upper and lower halves for slidablymounting therein. The openings and blade member rearward portions may beconfigured for a frictional and non-rotational fit therebetween. Thespring contacts may be in biased engagement with the blade memberrearward portions. The spring contacts may be formed of wire for lowmanufacturing cost. The spring contacts may include a flexing spring armportion and a torsion spring portion for contacting the blade membersand may include a portion designed to snap-fit within the internalcircuitry for assembly ease. The spring arm portion may extend in alongitudinal direction and be resiliently flexible in a lateraldirection thereto, and shifting of the spring arm portion from a naturalposition by the blade members may create a contacting force therebetweenfor providing and maintaining electrical connection between the springcontact and its respective blade member. The spring contacts may alsoinclude a portion secured with the internal circuitry to resist rotationof the snap-fit portion. The spring arm may include a forwardlyextending portion for biased engagement with the blade members. Thespring contacts may further include a torsionally flexing spring armportion for providing an elastic contacting force with the blademembers.

In some forms, the input assembly may include the prong portions beingsecured without molding such as insert molding.

In some forms, the electrical connection between the input assembly andthe spring contacts is solder-less.

In another aspect, a charger plug providing power conversion forrechargeable electronic devices is disclosed, the charger plug includinginternal circuitry for converting input electrical power to outputelectrical power including a plurality of components for powerconversion mounted on at least one board and including electricalconnections for receiving power, an input assembly including first andsecond blades having prong portions for connecting with a power outletand transmitting input electrical power to the internal circuitry viathe electrical connections, and a housing defining an interior space forthe internal circuitry and slidably mounting the input power assemblytherewithin and in electrical communication with the electricalconnections, the electrical connections being forwardly biased intoengagement with the blade members.

In some forms, the blades are separate members having a rearwardstructure with a rearwardly oriented surface, the housing includesopenings for slidably receiving portions of the blades, and theelectrical connections are forwardly biased into engagement with therearwardly oriented surface.

In some forms, the housing includes upper and lower halves, each of thehalves includes openings for receiving generally vertically oriented legportions of the blades, and each of the halves includes slots forforwardly extending prong portions.

In a further aspect, a charger plug for converting input alternatingcurrent power received from a power outlet to output direct currentpower, the charger plug being electrically connectable to a rechargeableelectronic device for providing power thereto, is disclosed, the chargerplug including a housing having a first end oriented towards a poweroutlet when connected thereto and a second end extending in a firstdirection away from the first end, and first and second separate blademembers secured with the first end of the housing so as to have prongportions extending in the first direction from slots formed in thehousing, the blade members having mounting portions extending in asecond direction that is transverse to the first direction, wherein thehousing includes openings for slidably receiving the mounting portions.

In some forms, each of the blade members is shaped with a prong portionextending in the first direction, with an elbow portion connected withthe prong portion, and with the mounting portions connected to the elbowportion, wherein at least either the elbow portion or the prong portionextends through the slots. The housing may include upper and lowerhalves, the blade mounting portions may have generally rectangularcross-sections, each of the halves may include respective openings ofgenerally rectangular cross-section for receiving the rectangular blademounting portions, and the slots may be defined by slot portions of bothof the halves.

In some forms, the charger plug includes internal circuitry forconverting the power, the internal circuitry having a board forsupporting components thereon, the board including an elongated slot andan opening, and spring contacts formed of wire and including acompressible elbow portion for snap-lit receipt in the elongated slotand including an extending portion received in the board opening forresisting forces on the spring contacts, wherein the spring contacts arebiased into engagement with the blade members for electrical connection.

In some forms, the charger plug is sized so as not to impede access toor use of an adjacent outlet.

In some forms, the charger plug includes a power cord mounted at thesecond end of the housing for providing output power to the electronicdevice. The charger plug may include a connector for connecting with apower cord to provide output power to the electronic device. Theconnector may be mounted for connecting with the power cord proximatethe second end of the housing. The blades may be connectable with thepower outlet when advanced in said first direction and be removable fromthe power outlet when advanced in a direction opposite said firstdirection, and the power cord may be electrically connectable with theconnector when advanced in said first direction and be removable fromthe connector when advanced in said direction opposite said firstdirection. The connector and blades may be generally aligned relative toeach other.

In a still further form, a method of assembling a charger plug forconverting input electrical power to output electrical power isdisclosed, the method comprising the steps of providing a pair of blademembers including a first portion in the form of a prong for each ofnegative and positive terminals of the charger plug and including asecond portion for mounting, forming a housing having at leastrespective openings for receiving the second portion of each of theblade members in an interior of the housing and having at least a slotfor permitting the prong of each blade to extend forwardly from thehousing for connection to an electrical outlet, providing internalcircuitry for power conversion, the internal circuitry including a boardfor supporting components thereon, for each of the positive and negativeterminals, providing a spring contact member having a spring arm,mounting the spring contact members on the board in electricalconnection with the internal circuitry, slidably inserting the secondportion of each blade member in the interior openings of the housing formounting the blade members therewith, after the slidably inserting steppressing the spring contacts against a rearward surface of the blademembers to shift the spring arms towards the board, and after thepressing the spring contacts step closing the housing.

In some forms, the method further includes the step of, after thepressing the spring contacts step pivoting the board towards the housingto bring the board into registry with structure on the interior of thehousing.

In an additional aspect, a charger plug is disclosed for connecting witha power outlet to converting input current power received from the poweroutlet to output current power, the charger plug being electricallyconnectable to a rechargeable electronic device for providing the outputcurrent power thereto, the charger plug including a housing having afirst portion oriented towards a power outlet when connected thereto anda second portion, the charger plug including first and second separateblade members secured with the first portion of the housing so as tohave prong portions of the blade members extending in the firstdirection from the housing, and the charger plug including a connectorat the second portion of the housing, the connector adapted forremovably receiving a corresponding apparatus for transmitting power tothe electronic device, the improvement of the charger plug being theconnector is aligned with the prong portions, and the connectorreceiving the corresponding apparatus in a direction substantiallyopposite the first direction.

In some forms, the improvement may also include the housing having atapered portion at a rear end thereof, the tapered portion having anopening, and the connector being accessible through the tapered portionopening. In some forms, the charger may include a supporting substrateon which internal circuitry for converting power is mounted, and theimprovement may also include the supporting substrate being a boardextending in a lateral direction relative to the prong portions, theconnector is mounted on the board, and the housing has a shape toprovide a tactile indication of an orientation of the connector.

BRIEF DESCRIPTION OF THE DRAWINGS

In the Figures, FIG. 1 is a rear perspective view of a plug of thepresent invention showing a connector opening at a rear end of the plugfor receiving a connecting cord for electrically coupling the plug withan electronic device, prongs of blades extending from a forward end forreceipt into an electrical outlet for receiving power therefrom;

FIGS. 2A-2C are exploded perspectives of the plug of FIG. 1 showing apair of blades including the prongs, an internal circuitry assembly forpower conversion including a printed circuit board and the connectorbeing mounted thereon, spring contacts mounted on the printed circuitboard for electrically coupling the blades to the printed circuit board,and housing upper and lower halves for receiving the blades and internalcircuitry;

FIG. 3 is a perspective view of the plug of FIG. 1 with the lowerhousing half removed to show the spring contacts coupled with the bladesmounted in the upper housing half;

FIG. 4 is a perspective view of the plug of FIGS. 2A-2C with the upperhousing half removed to show the spring contacts coupled with the bladesmounted in the lower housing half, a power cord coupled with theconnector for providing power to an electronic device;

FIG. 5 is a perspective view of the blade of FIG. 1;

FIG. 6 is a top plan view of the blade of FIG. 1 with a partial cut-awayto show a configuration of a bore therethrough;

FIG. 7 is a perspective view of the upper housing half showing structurefor positioning the printed circuit board therewithin, showing slots forreceiving the blades to secure the blades and permit a prong portionthereof to extend from the upper housing half, and showing a peripheralshoulder formed for receiving the lower housing half;

FIG. 8 is a bottom plan view of the upper housing half showing aconfiguration of the slots and showing blind openings for receiving andpositioning the blades therewithin;

FIG. 9 is an enlarged view of detail 9 of FIG. 8 showing theconfiguration of one of the slots to accommodate the configuration ofthe blade received therein;

FIG. 10 is a front elevation view of the upper housing half;

FIG. 11 is a cross-sectional view taken through the line 11-11 of FIG.10 showing the configuration of one of the slots thereof;

FIG. 12 is a perspective view of the lower housing half showingstructure for receiving the printed circuit board therewithin, showingslots for receiving the blades to secure the blades and permit a prongportion thereof to extend from the upper housing half, and showing aperipheral tongue for receipt into the upper housing half;

FIG. 13 is a top plan view of the lower housing half showing aconfiguration of the slots for the prong portions and showing blindopenings for receiving and positioning the blades therewithin;

FIG. 14 is an enlarged view of detail 14 of FIG. 13 showing theconfiguration of the slots to accommodate the configuration of the bladereceived therein;

FIG. 15 is a front elevation view of the lower housing half;

FIG. 16 is a bottom plan view of the internal circuitry showing theshape of spring arms of the spring contacts, showing a recess permittingthe spring arms to shift rearwardly when pressed into the blades wherebybias of the spring contacts maintains the spring contacts inelectrically communication and coupling with the blades;

FIG. 17 is a perspective view of the relative positioning and theconfiguration of the spring contacts in a natural state, the springcontacts having an elbow portion for snap-fitting into the printedcircuit board;

FIG. 18 is a front perspective of the printed circuit board with thespring contacts secured therewith; and

FIG. 19 is a front elevation view of a label positionable against afront surface of the assembled plug.

FIG. 20 is a schematic representation of a power cord mateable to acharger plug of the present invention mateable to a standard NEMAoutlet.

DETAILED DESCRIPTION

Referring initially to FIGS. 1-4, a plug 10 having a reduced packagesize and improved manufacturing is illustrated, the plug 10 preferablybeing a AC to DC charger plug for converting input electrical power tooutput electrical power, thereby providing charging power torechargeable portable electronic devices or the like. As can be seen,the plug 10 benefits from a structure and method of assembly provided byan input assembly 11 which, in the present form, includes a pair ofblades 12 having prong portions 50, discussed below. The blades 12 arereceived by a housing 14, and the plug 10 further includes springcontacts 16 for electrically connecting the blades 12 with internalcircuitry 18 of the plug 10.

In the present form, the housing 14 is a clamshell-type housing havingupper and lower halves 22 and 24. The internal circuitry 18 and blades12 are assembled into one of the halves 22, 24, and the halves 22, 24,are then secured together such as by electronic welding or by asnap-fit, as are known in the art.

In the present form, the internal circuitry 18 includes a supportingsubstrate, such as a board 30 which is preferably a printed circuitboard (PCB), onto which electronic components 32 are secured andassembled, the components 32 being supported thereon. The components 32preferably include a power conversion circuit for receiving an inputalternating current (AC) voltage, for reducing the voltage, forconverting the AC to direct current (DC), and fin transmitting the DCwith the reduced voltage to an output 34. In the present form, thecomponents 32 include a connector 36 for coupling with a removable powercord 37, the power cord 37 in turn able to be coupled to an electronicdevice (not shown) for providing the reduced voltage DC power to theelectronic device. When assembled, the connector 36 is positioned at arear end 40 of the housing 14, and the housing 14 is preferably taperedfrom lateral sides 42 and from upper and lower sides 44 towards aconnector opening 46 configured in registry with the connector 36 toprovide access to the connector 36. This tapering minimizes weight andmaterials cost, as well as provides a desirable aesthetic for the plug10.

In greater detail, it can be seen that that the blades 12 and housing 14provide a direction of insertion into a power source (outlet or powerstrip having one or more receptacles), the plug 10 being advancedtowards the outlet in the insertion direction so that the blades 12 arereceived in the outlet and the plug 10 being withdrawn or advanced awayfrom the outlet in an opposite, removal direction to remove the blades12 from the outlet. The connector 36 allows for the power cord 37 to bereceived therein by advancing the power cord 37 in the same insertiondirection, and the power cord 37 to be removed from the connector 36 inthe same opposite, removal direction. The power cord 37 includes a plugend 37a that is receivable and removable from the connector 36 and, in apreferred form, the extent of advancement in the insertion or removaldirections for the plug end 37a relative to the connector 36 is lessthan the extent of advancement of the blades 12 for insertion or removalfrom the power outlet. In this manner, once the plug 10 is received inthe power outlet, it is easier (i.e., requires less space and movement)to disconnect the power cord 37 from the plug 10 than it is to removethe plug 10 from the power outlet. The configuration of the connector 36relative to the blades 12 also allows the plug 10 to be secured withand/or removed from the power outlet by advancement through a relativelysmall space (e.g., minimal clearance in directions lateral to thedirections of insertion/removal), and the power cord 37 can beconnected/removed through the same relatively small space. In the mostpreferred form, the connector 36 is positioned in the plug 10 so that itis aligned with the blades 12.

Turning to FIGS. 5 and 6, one of the blades 12 is illustrated. The plug10 is provided with a pair of blades 12 for connection with a standardpower outlet, i.e., 120 VAC. In order to simplify parts and assembly, itis preferred that the each of pair of blades 12 is identical to theother, though reversed in orientation when secured in the plug 10. Ascan be seen the blade 12 includes a prong portion 50 with a size andshape known in the art to include a beveled terminus 52 and a bore 54.

The blade 12 is generally formed integral as a unitary item and,preferably, is a simple cut and stamped component. The cold-working ofthe stamped blade 12 provides rigidity and strength to the blade 12. Theprong 50 extends from the terminus 52 rearwardly to an elbow portion 56that forms an arc of 90 degrees. As can be seen, the blade 12 in thehorizontal direction has uniform thickness throughout, other than theterminus 52 and bore 54, though such may be varied according to designcriteria such as for reducing materials.

The elbow 56 is joined to a vertical bar portion 60 having a greatervertical dimension than the elbow 56 and prong 50 so that the bar 60forms first and second legs 62 and 64 which, depending on orientationwhen assembled, serve as either upper or lower legs. As will bediscussed below, the legs 62, 64 are received in one of either the upperor lower housing halves 22, 24. Additionally, when assembled, the bar 60is electrically connected with a spring contact 16, preferably by biasedengagement between the spring contact 16 and a rearwardly oriented andvertical surface 60a of the bar 60, as can be seen in FIG. 3.

Turning to FIGS. 7-11, a form of the upper housing half 22 isillustrated. The upper housing half 22 partially defines an interiorregion 70 into which the internal circuitry 18 is positioned duringassembly. Extending from an internal surface 72 of the half 22 is aplate 74 which assists in registry of the half 22 with the PCB 30 whichhas a slot 76 for receiving the plate 74. A rear end 78 of the half 22includes a tapered region 80, as described above, that forms a portionof the connector opening 46. The half 22 includes generally radiusedsides 82, which serve to reduce packaging size and materials as well aspromotes removal from the mold assembly, and interior runners 84 thatprovide rigidity to the plug 10, and that provide registry for the PCB30 (as can be seen in FIG. 3). Additionally, it should be noted that thehalf 22 has a peripheral wall 86 and an interior shoulder 87 formedtherewith, the runners 84 extending downward beyond the shoulder 87 todefine a recess 88 between the wall 86 and the runner 84 for receiving atongue 89 formed on the lower housing half 24, as will be discussedbelow.

A front end 90 of the upper housing half 22 includes structure 92 forreceiving, positioning, and somewhat securing blades 12 therewith. Ingeneral, the structure 92 includes portions defining a slot 94 whichreceives and constrains the blade 12 at or about the elbow 56 and/or theprong 50, and the structure 92 includes portions defining a blindopening 96 for receiving one of the legs 62, 64, as can be seen in FIGS.3 and 4.

With particular emphasis on FIGS. 8 and 9, the slot 94 passes throughfrom a front surface 100 of a front wall 102 to a rear surface 104thereof. An inboard side 106 of the slot 94 includes a structure 108,shown as a bevel or chamfer, for accommodating and, preferably, abuttingan inner curve side 110 of the elbow 56 to provide constraintthereagainst. While the structure 108 may be curved to match the elbow56, such would require greater precision in tolerances withoutappreciable constraining benefit. An outboard side 114 of the slot 94simply includes a generally flat surface 116 that merely need makecontact with an outer surface 118 of the prong 50 and/or elbow 56.

The blind opening 96 preferably has a non-circular cross-sectional shape120 and is preferably shaped to receive a blade leg 62, 64 in arelatively defined position. More preferably, the legs 62, 64 arerectangular in cross-sectional shape, the blind opening shape 120 isrectangular having walls 120a-12d, and the blind opening 96 is sized toreceive a leg 62, 64, therein with a small amount of friction between atleast two of the walls 120a-120d and the leg 62, 64 received therein,and the blade bar 60 is thus generally vertically aligned in a directiontransverse to the direction that the plug 10 generally extends.

Referring now to FIGS. 12-15, a form of the lower housing half 24 isillustrated with similar structures as the upper housing half 22.Specifically, the lower housing half 24 partially defines the interiorregion 70 into which the internal circuitry 18 is positioned duringassembly, includes a rear end 130 having a tapered region 132 forming aportion of the connector opening 46, includes generally radiused sides134, and interior runners 136. In contrast to the upper housing half 22,the lower housing half 24 includes an exterior shoulder 137 positionedoutside of the aforementioned tongue 89, the interior runners 136 joinedwith the tongue 89 to provide rigidity thereto. When assembled, thetongue 89 and runners 136 are received within the peripheral wall 86 ofthe upper housing half 22, the tongue 89 being received between theperipheral wall 86 and the upper runners 84. Depending on designcriteria, the tongue 89 may be advanced within the peripheral wall 86 toan extent that a tongue top surface 89a contacts the shoulder 87, thoughthis is not necessary. In alternative forms, the tongue 89 andperipheral wall 86 may be provide with snap fit structure, though in thepresent form the upper and lower housing halves 22, 24 areelectronically welded or glued.

Comparing FIG. 10 showing the upper housing half 22 and FIG. 15 showingthe lower housing half 24, it can be seen that the lower housing half 24has a vertical dimension 150 that is greater than a vertical dimension152 of the upper housing half 22, except for the plate 74. The greaterdimension 150 is a result of the protruding tongue 89. However, avertical dimension 154 of the lower housing half 24 from a bottom side156 to the shoulder 137 is roughly approximate the vertical dimension152 of the upper housing half 22 from a top side 160 to a top surface162 of the peripheral wall 86.

Like the upper housing half 22, the lower housing half 24 includesstructure 170 for receiving, positioning, and somewhat securing blades12 therewith. The structure 170 generally includes portions defining aslot 172 (the slot 172 being greater in vertical dimension that slot 94of the upper housing half 22 due to the need for the slot 172 to passthrough the tongue 89) which receives and constrains the blade 12 at orabout the elbow 56 and/or the prong 50, and the structure 170 includingportions defining blind openings 96 for receiving one of the legs 62, 64in a manner substantially identical to that of the upper housing half22.

With particular emphasis on FIGS. 13 and 14, the slot 172 passes throughfrom a front surface 180 of a front wall 182 to a rear surface 184thereof. An inboard side 186 of the slot 172 includes a structure 188,shown as a bevel or chamfer, for accommodating and, preferably, abuttingan inner curve side 110 of the elbow 56 to provide constraintthereagainst, while an outboard side 190 may have a flat surface 192,each feature of which being similar to that described for slot 94 of theupper housing half 22.

The upper and lower housing halves 22 and 24 cooperate to constrain thevertical position of the PCB 30. As can be seen in FIGS. 7 and 8, theupper housing half 22 includes supports 194 against which the PCB 30rests when the plug 10 is assembled. The runners 137 136 of the lowerhousing half 24 contact the PCB 30 from an opposite side as the supports194 so that the PCB 30 is somewhat constrained or lightly sandwichedbetween the runners 137 136 and supports 194.

Turning now to FIGS. 16-18, the internal circuitry 18 and springcontacts 16 are illustrated. As discussed above, the internal circuitry18 preferably includes a PCB 30 and a pair of spring contacts 16. Thespring contacts 16 are simply formed of wire and, thus, are much lessexpensive than contacts made by other means, such as stamped components.As the spring contacts 16 are used with respective blades 12, the springcontacts 16 are electrically isolated from one another. Each springcontact 16 includes a first extent 200 received in an opening 202 of thePCB 30, a second extent 204 running along a surface 206 of the PCB 30when secured therewith, an elbow barb 208 received in an elongatedopening 210 of the PCB 30, and a spring arm 212 extending from the barb208. The spring arm 212 extends in a generally longitudinal manner, andextends generally parallel to the PCB 30, with the arm end 212a free sothat the spring arm 212 is resiliently deflectable and/or flexible. Thisflexibility allows the spring arm 212 to provide a resilient bias forcewhen deflected laterally from its natural position. The barb 208 issnap-fit into the elongated opening 210 such that the barb 208 iscompressed inwardly and ramps over a barb point 208a as the barb 208passes into the elongated opening 210. Thus, compression is required toremove the barb 208 and spring contact 16 from the PCB 30. Preferably,the barb 208 received in the PCB 30 is under compression so thatfriction between the barb 208 and PCB 30 reduces likelihood of shiftingof the spring contact 16.

When the spring contact 16 is secured with the PCB 30, the blade bar 60is received forward of the spring arm 212 and, to an extent, in a recess220 formed at a forward edge 222 of the PCB 30, though otherconstructions could be utilized. When assembled as such, the spring arm212 is shifted from its natural position and rearwardly into the recess220 so that the forward bias of the shifted spring arm 212 serves tomaintain the spring arm 212 and blade bar 60 in electrical connection.As can be seen, the spring arm 212 further includes a forwardlyextending elbow 230 to provide additional bias force when the blade bar60 contacts and forces the elbow 230 rearwardly. The bias force betweenthe spring arm 212 and the blade bar 60 tends to cause a torque orrotation around a vertical axis. Accordingly, the first extent 200serves to minimize the ability of the spring contact 16 to rotate whenthe plug 10 is assembled.

The shifting or deflection of the spring arm 212 is properly understoodas a leaf spring, as a torsion spring, or as a combination of both, thespring contact 16 providing elastic contact force as described herein.That is, the spring arm 212 is resiliently deflectable in the manner ofa leaf spring. The spring arm 212 is also secured or integral with thebalance of the spring contact 16 that is secured with the PCB 30, whichis secured in an offset manner relative to the direction of longitudinalextent of the spring arm 212. Therefore, when the spring arm 212 isshifted from its natural position, a torque is experienced between thespring arm 212 and, in the present form, the barb 208 secured in theelongated opening 210. Due to this torque, the operation of springcontact 16 (or, the cooperation between the spring arm 212 and the barb208) can be viewed as a torsion spring for contacting the blade members.

Turning to FIGS. 2A-2C and 19, a label 240 having openings 241 for theprongs 50 is illustrated. Generally, regulatory bodies require anindication of certain information regarding electrical devices. Thelabel 240 provides an easy and simple manner in which to provide thisinformation, yet has additional benefits. For instance, by placing thelabel 240 on the front end of the plug 10, on front surfaces 100 and180, the plug 10 has an improved aesthetic as such information is notvisible by a user when the prongs 50 are received in a power outlet. Theuse of the label 240 allows the housing 14 to be used with charger plugshaving a variety of ratings (i.e., output voltages) without separatehousings 14 to be molded for each. Additionally, as the label 240 isprovided with glue or pressure-sensitive adhesive, for instance, thelabel 240 may be used for assembly purposes by spanning the seam betweenthe upper and lower halves 22, 24 at their front surfaces 100, 180.

An improved method of assembly is provided by the plug 10. The PCB 30and the components 32 located thereon are provided as an assembly 250,and a pair of spring contacts 16 are mounted therewith so that the barb208 is received in the elongated opening 210 and the first extent 200 isreceived in the opening 202. Separately, the upper housing half 22 isprovided and, a pair of blades 12 are mounted therewith by advancing oneleg 62, 64 of each blade 12 into the blind openings 96 with a frictionalfit. Continued advancement of the blades 12 brings the elbow 56 andprong 50 into the slot 94. The PCB assembly 250 is then positioned withthe spring contact spring arms 212 against a backside of the blade bars60, the PCB assembly 250 being inclined with respect to the upperhousing half 22 so the connector 36 is positioned above and out of theconnector opening 46 portion of the rear end 78. Pressure is applied tothe PCB assembly 250 towards the blades 12 so that the spring arms 212are shifted rearwardly toward the PCB 30, creating a bias forcetherebetween. Subsequent or simultaneous with applying the pressure, thePCB assembly 250 is rotated or pivoted (the spring arms 212 generallyproviding the pivot or center of rotation) into the half 22 until therunners 84 are received within notches 252 formed in the PCB 30. The PCBassembly 250 is thus compressed somewhat between the runners 84 and theblade bars 60. The lower housing half 24 is then positioned with itsinterior open to the internal circuitry 18, and the blind openings 96 ofthe lower housing half 24 are aligned with the other legs 62, 64 of theblades 12. The lower housing half 24 is then advanced towards the upperhousing half 22 so that the legs 62, 64 are received within the blindopenings 96 thereof, and the elbow 56 and/or prong 50 is received withinthe slots 172. With continued advancement, the tongue 89 and peripheralwall 87 and related structures are brought together in the mannersdescribed above. The halves 22 and 24 are then joined such as byelectronic welding, glue, use of the label 240, other known manners, ora combination thereof.

It should be noted that, as described, the dimensional size of the plug10 at the front surfaces 100, 180 is small enough that the plug 10 doesnot interfere with use of an adjacent plug, such as is known for two- orthree-outlet receptacles as defined by NEMA standards.

It should also be noted that the plug 10 locates the connector 36 andthe opening 34 thereof in line with the prongs 50. To be specific, it isknown that a typical device connected to a power outlet, such as a lampor television, includes a plug, blades extending from the plug, and acord extending from the plug in a direction opposite the blades. Anexample of a prior art charger having a receptacle, similar to thedescribed connector 36 and connector opening 34, is that which isprovided by Apple, Inc., for some of its popular IPod music playerdevices. When looked at from a side of the prongs, the Apple chargerincludes a relatively large housing with a somewhat square profile. Thehousing sufficient extends, relative to the prongs, so that the chargerreceived in a power outlet could interfere with an adjacent receptacle,and would likely interfere with an adjacent receptacle on a power strip.Viewed in another direction, the charger housing is generally anelongated rectangle, a shape that conforms to the orientation of amotherboard or PCB therein for mounting of the charger components. Theprongs of the Apple charger are pivotable, a feature designed to promotethe portability of the charger, such as in a backpack.

As stated above, the Apple charger has a receptacle for connectablyreceiving a cord. However, the purpose of this is somewhat differentthan that suggested herein: the IPod device originally provided a singleport for communication with a computer and for communication with apower source. That is, a IEEE 1344 or Fire Wire cord could be connectedto the single port and, then, either connected to the charger or to acomputer. Accordingly, the Apple charger was simply concerned with beingable to remove the cord from the charger so that the same cord couldthen be connected to the computer. In other words, little attention waspaid to the charger itself, aside from the pivotable prongs and theconnectability feature. Additionally, the size and shape of the Applecharger are generally dictated by the internal components thereof,including the PCB.

The present plug 10 overcomes a number of deficiencies of the Applecharger and other prior art. For example, the plug 10 allows the plug 10itself to avoid interfering with an adjacent receptacle of a wall outletor of a power strip. This is achieved in a number of manners, includingthe configuration of the internal circuitry 18 and the size and shape ofthe plug housing 14. The present plug 10 has the blades 50 aligned withthe opening 34, thereby presenting greater stability, also due to theconfiguration of the internal circuitry 18 and the PCB 30 and thehousing 14, so that the connector 36 is mounted in centered alignmentwith the blades 50, both in vertical and horizontal directions. Asdiscussed herein, the alignment of the connector 36 and opening 34 withthe blades 50 allow the cord 37 to be easily connected with and removedfrom the plug 10 through relatively small spaces and without interferingwith the use of adjacent outlets. While the surface of the Apple chargerreceiving the cord is flat, in the present plug 10 includes the taperedrear end 40 to assist a user with manually and tactiley locating,identifying, and connecting the connector 36 with the cord 37, as wellas relative orientations of each, as may be necessary when reaching intoa small space or when visual identification is difficult or impossible.

In a preferred form, the connector 36 is a mini-USB connector, thoughany type of connector may be used. As such, the plug 10 may be usablewith a variety of cords 37, each having a standard plug end 37a, so thateach of the cords 37 may connect the plug 10 with a particular device.In other words, a single plug 10 may be provided with a plurality ofcords 37, and each of the cords 37 can be provided with a first end 37afor receipt into the connector 36, and with a second end (not shown) forconnecting with a particular device, such as a particular make and modelof cell-phone. Therefore, a person having multiple devices that may beused with plug 10 may each be connected with the connector 36 via thedifferent cords 37. As examples of the utility of this, a traveler mayreduce the chargers he or she must bring to a single charger, a personpurchasing a new rechargeable device can simply buy an inexpensive cord37 for connecting to the charger plug 10 for use with the device, and aperson replacing a device need not also replace the charger.

While it is known in the art to provide one or more connectable cordsfor a single charger, it is not believed that any prior art chargerhaving such feature is able to provide the stability and ease of useprovided by having the connector opening 34 for accessing the connector36 aligned with the blades 50, is able to provide a plug that permitsuse of the adjacent power outlets when connected, and provides a shapefor the housing 14 and orientation of the opening 34 such that a usereasily recognizes, such as without being able to visually inspect theplug 10, the proper orientation of the plug 37 when attempting toconnect with the plug 10. To promote this, the PCB 30 is mounted in alateral direction relative to the direction of the prongs 50 and theconnector 36; in other words, while the prongs 50 and connector 36extending in opposite directions and are respectively coupled with theoutlet and cord 37 by movement along a general line, albeit in oppositedirections, the generally planar PCB 30 is mounted in the housing 14 sothat its plane extends between the prongs 50 and connector 36, as wellas so that, were the plug 10 oriented so the upper housing half 22 isvertically oriented relative to, and directly above, the lower housinghalf 24, the PCB 30 is oriented in a horizontal manner.

As described, the plug 10 provides a number of benefits. The plug 10size is reduced as the extent of the blades 12 beyond what is necessaryfor the prongs 50 is merely the size of the blade bar 60 and thethickness of the front walls 102, 182. The spring contacts 16 havelittle forward-to-rear directional dimension. The dimensional reductionover the aforementioned '984 patent is approximately 2-4 mm.Additionally, by not soldering the blades 12 to the spring contacts 16,package space required for soldering is eliminated, as are the laborcosts and the risks of damage due to solder, the plug 10 can easily bedisassembled if it is determined that one of the internal circuitrycomponents 32 is defective, and the space on the PCB 30 required forelectrical connection to the blades 12 is minimized. By securing theblades 12 in the manner described, the problems of insert molding or thelike are eliminated. The reduced package size and steps of assemblyreduce materials and labor required to manufacture and assemble thecomponents and the plug 10 as a whole. The use of wire for the springcontacts 16 is a significant cost and materials savings over thecomplicated stamped components of the prior art. By way of example, thelateral width of the plug housing 14 is less than 1.75 inches, andpreferably approximately 1.35 inches; the overall longitudinal length ofthe housing 14 is less than 2.0 inches, and preferably approximately1.75 inches; and the height of the housing 14 is less than 1.0 inches,and preferably approximately 0.7 inches.

While the invention has been described with respect to specific examplesincluding presently preferred modes of carrying out the invention, thoseskilled in the art will appreciate that there are numerous variationsand permutations of the above described systems and techniques that fallwithin the spirit and scope of the invention as set forth in theappended claims.

What is claimed is:
 1. A charger plug capable of connecting with a twoor three receptacle power source to convert 120V input power receivedfrom the power source to DC output power, the charger plug beingelectrically connectable to a rechargeable electronic device via a powercord for providing the DC output power thereto, the charger plugincluding a housing, the charger plug comprising: first and secondseparate blade members secured within the housing so as to have prongportions of the blade members positioned in order to extend in a firstdirection from a front wall of the housing, the prong portions adaptedto be received in the receptacle openings of the power source; thecharger plug including a DC connector having an aperture adapted toremovably receive a corresponding power cord plug end for transmittingDC power to the rechargeable electronic device; the charger plug housingforming a) a charger plug face area defined by the front wall b) anouter profile defined by a perimeter of the front wall and defined by aplug body extending rearward from the front wall and c) a rear endopposite the front wall; the charger plug configured to be capable ofplugging into a standard wall outlet and further: i) being sized so thatthe charger plug housing comprises a longitudinal length extendingbetween the front wall and the rear end and the longitudinal length isequal to or less than 2.0 inches, a width of the housing outer profilebeing less than 1.75 inches, and ii) the outer profile having nointerference with an adjacent receptacle of the power source located onall sides of the first receptacle when a like charger plug is mounted inall available orientations in any of the other receptacles, so that whenspace is limited by an obstacle adjacent or in front of the power sourcethe charger plug is capable of being conveniently mounted to one of thereceptacles, the power cord plug end may be conveniently received by theDC connector and the power cord plug end can be conveniently removedfrom the DC connector while leaving the charger plug connected to thereceptacle.
 2. The charger plug of claim 1 wherein the charger plug facearea has a perimeter that defines generally one of a polygonal,squared-off circle, ovoid or circular shape and the receptacle face areahas a periphery that defines generally one of a polygonal, squared-offcircle, ovoid or circular shape.
 3. The charger plug of claim 2 whereinthe perimeter of the charger plug defines a footprint that is not thesame shape as the periphery of the receptacle.
 4. The charger plug ofclaim 2 wherein the periphery of the receptacle surrounds less than allsides of a group of the receptacles.
 5. The charger plug of claim 4wherein the power source comprises a receptacle having two or threegroups of receptacle openings disposed in a single continuous platecomprising the first and second receptacles.
 6. The charger plug ofclaim 1 wherein the power source comprises four receptacles disposed inthe wall outlet.
 7. The charger plug of claim 1 wherein the power sourceincludes three receptacle openings disposed in each of the first, secondand third receptacles.
 8. The charger plug of claim 1, furthercomprising the housing having a tapered portion at a rear end thereof,the tapered portion having an opening, and the connector beingaccessible through the tapered portion opening.
 9. The charger plug ofclaim 1, further comprising a supporting substrate on which internalcircuitry for converting power is mounted, the supporting substratebeing a board extending in a lateral direction relative to the prongportions, and the housing has a shape to provide a tactile indication ofan orientation of the connector.
 10. The charger plug of claim 1 whereinthe housing forms an outer profile having a longitudinal length of thehousing outer profile being less than approximately 2.0 inches and awidth of the housing outer profile being less than approximately 1.7inches height of the housing outer profile being less than 1.0 inches.11. The charger plug of claim 1, wherein the connector is USBreceptacle.
 12. The charger plug of claim 1, wherein the aperture of theconnector for receiving the power cord plug end has an insertion depththat is less than an insertion depth of the receptacle of the powersource, the insertion depth of the receptacle being defined by the blademembers of the charger plug being measured between an exit point wherethe blade member exits the housing and a terminal point on the blademember furthest from the exit point, so that the power cord plug end canbe conveniently removed in a small space leaving the charger plugconnected to the receptacle.
 13. The charger plug of claim 1 wherein theconnector is positioned on the housing so that a second direction ofinsertion of the connector aperture is substantially in-line with thefirst direction of the blade members of the charger plug to provide ashorter travel path for inserting and removing the power cord plug endwhen space is limited by an adjacent obstacle.
 14. The charger plug ofclaim 1 wherein the charger plug includes a rear end on a side oppositethe front wall and the connector is positioned on the housing so that asecond direction of insertion of the connector aperture is substantiallyperpendicular with the first direction of the blade members of thecharger plug to provide a shorter travel path for inserting and removingthe power cord plug end when space is limited by an obstacle adjacentthe rear end of the charger plug.
 15. The charger plug of claim 1,wherein the power source comprises a power strip having multiplereceptacles aligned side by side along the power strip.
 16. The chargerplug of claim 1, wherein the power source comprises a wall outlet. 17.The charger plug of claim 1, wherein the charger plug includes the DCconnector oriented in order to provide a first removal force to removethe power cord plug end from the DC connector that is less than a secondremoval force to remove the blade members from the receptacle openingsof the power source.
 18. The charger plug of claim 1, wherein the DCconnector has an aperture adapted for removably receiving acorresponding power cord plug end for transmitting DC power to theelectronic device, the power cord plug end insertable within theaperture along a second longitudinal insertion axis of the connectoraperture that is substantially in-line with the first direction.
 19. Thecharger plug of claim 1, wherein the blade members are non-movablymounted to the housing.
 20. The charger plug of claim 1, furthercomprising a power conversion circuit disposed within the housingoperatively connected to the prong portions of the blade members forreceiving the 120V input power from the power source and converting itto the DC output power for supply to the DC connector.
 21. The chargerplug of claim 20, further comprising a label on the exterior of thehousing with information relating to requirements of applicableregulatory bodies.
 22. The charger plug of claim 1, further comprising alabel on the exterior of the housing with information relating torequirements of applicable regulatory bodies.